Biocides, and in particular pesticides such as fungicides, insecticides and herbicides, are important auxiliary agents for agriculture in order to protect and to increase crops yields. Depending on the various and often very specific needs a magnitude of actives exist which show very different chemical structures and behaviors. Nevertheless, it is well known from the state of the art that it remains difficult to prepare concentrates of these actives which are exhibiting a satisfying stability, especially if stored at very low or elevated temperatures over a longer period. As a matter of fact, the solutions show a strong tendency to either separate or to form crystals, which makes it necessary to re-disperse the actives in the compositions prior to every application in order to obtain a homogenous product. Due to the fact that in spray equipments, which are customarily used for the application of aqueous formulations of plant treatment agents, several filters and nozzles are present, an additional problem appears which is related to the blocking of these filters and nozzles as a result of crystallizing active compound during the application of aqueous spray liquors based on solid active compounds.
The use of certain derivatives of lactic acid, in particular lactamides is well known from the state of the art. For example, German patent application DE 4112873 A1 discloses a composition comprising a fungicide (triflorine), lactic acid dimethyl amide and an emulsifier. The use of various lactamides as solvents in agriculture is described in WO 2006/040022 A2 (Bayer), WO 2007/107745 A2 (Syngenta), or EP 1961301 A2 (Cognis).
Products generally found in the market present either a limited content of biocides and/or hazardous labeling and a non favorable eco-toxicological profile.
The problem underlying the present invention has been to identify suitable new solvents for developing new biocide compositions with equal or higher contents of actives than obtainable in the market. The new solvents need to be safe and environmental friendly and should allow obtaining concentrated biocide compositions (on average more than 15% active matter) regardless of the chemical structure of the biocide, in other words they need to be excellent solvents for a wide range of herbicides, insecticides and fungicides. Finally, another object of the invention has been to design emulsifiable concentrates formulations with specific co-solvents and emulsifier system providing superior emulsion stability, in particular with respect to opacity and layering.